JP2964684B2 - Character data collection method for character reading - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention captures a plurality of unknown characters arrayed in a predetermined direction on each object, cuts out each character pattern based on the captured image, and sets a plurality of character patterns based on the extracted characters. The present invention relates to a character data collection method for improving the reading accuracy of a character reading device that reads characters from the degree of matching with a standard pattern, and more particularly to a character data collection method for optimizing a set value.

[0002]

Conventionally, as a method of improving the reading accuracy of the character reader, for example, it is such things known to explain below. That is, after the binarization level and the standard pattern are set, characters on the inspection object are first imaged in a stationary state, and the judgment is performed by matching with a plurality of preset standard patterns. At this time, judgment result data (read result, character size, area value, etc.) for each judgment
Is displayed on the monitor to correct the set value to an appropriate value. After such an operation is sequentially repeated while changing the characters on the inspection target, the characters on the inspection target transferred on the actual line are imaged, and the determination data on the monitor that changes continuously is taken. Finally, modify the setting value.

[0003]

As described above, in the prior art, after setting values are determined in advance, an image is taken in a stationary state, and it is determined whether or not the setting values are appropriate based on the result of the determination, and correction is made. Since the determination is made in the stationary state, the conditions may be different from those of the characters on the inspection object transferred on the actual line, and it is quite difficult to obtain a large amount of data. In addition, since the determination is continuously performed for different characters on the actual line, the data on the monitor switches at high speed, and there is a problem that it is extremely difficult to obtain necessary data. Therefore, an object of the present invention is to enable a large amount of data to be obtained even on an actual line.

[0004]

In order to solve such a problem, according to the first aspect of the present invention, a plurality of unknown characters arranged in a predetermined direction on an individual object are imaged, and the image is taken as an image. Based on the cut-out of each character pattern and the reading of characters based on the degree of matching between the character pattern and a plurality of preset standard patterns, a cut-out frame corresponding to at least one character position among the unknown characters, And a first step of designating at least one character that comes with a character (hereinafter referred to as a designated character), and selecting a character pattern similar to the designated character as a standard pattern from a plurality of preset standard patterns. A second step of performing the operation, and a data collection instruction for collecting data relating to the designated character designated in the first step, and a second step A third step of reading a character from the degree of matching with the selected standard pattern, a fourth step of determining whether the result of reading in the third step is one of the designated characters, and a fourth step A fifth step of, when the read result is identified as one of the designated characters, extracting a feature amount by taking a degree of matching of the designated character with the standard pattern selected in the second step; And a sixth step of storing the data extracted in the fifth step in a memory for each of the standard patterns set in the second step. The data stored in the sixth step can be displayed on a monitor. I have. According to the first aspect of the present invention, in the processing of the data, the acceptance of the determination regarding the next object is prohibited until the processing of all data is completed, and the determination of the next object is executed after the processing of all data is completed. Thus, data can be collected on an actual line (the invention of claim 2).

[0005]

[Function] By collecting the necessary data by designating the data collection mode, it is possible to easily collect a large amount of data based on a large number of determination results in the actual line, and display the data on a monitor as necessary. It is possible to correct the set value based on this data,
The reading accuracy can be improved as compared with the conventional one.

[0006]

1 shows a system to which the present invention is applied. In the figure, 1 is a television camera, 2 is a binarization circuit, 3 is an image memory, 4 and 6 are address generation circuits, 5 is a projection (projection) extraction circuit, 7 is a standard pattern memory, 8 is a matching circuit, 9 Denotes a processing device (CPU), 10 denotes a bus, 11
Is a character data display circuit, 12 is a monitor, 13 is a data memory, 14 is a read start receiving circuit, and 15 is a keyboard. An image pickup signal from the television camera 1 is binarized in a binarization circuit 2, and a pattern to be inspected is stored in an image memory 3.
The standard patterns are stored in the standard pattern memory 7, respectively. The address generating circuit 4 or 6 is used for the image memory 3
Alternatively, an address for scanning 7 is generated, and the projection extracting circuit 5 extracts projection (projection) data of the image read from the image memory 3 or 7 based on the scanning. The projection data is provided to the CPU 9, where individual character patterns are cut out. Each of the extracted patterns is stored in a standard pattern memory 7 by a matching circuit 8.
Are registered with all the standard patterns stored in. This collation result is compared with reference values (difference area, character size, perimeter) set in the CPU 9 in advance, and the consistency between the inspection target character pattern and the standard pattern is determined.

Now, _assuming that the objects H _{1 to} H _n on which the characters to be inspected as shown in FIG. 2 are printed flow on a real line, for example, FIG.
As shown in (a), to set the frame K ₁ ~K ₄ surrounding each character with a certain margin, cut out characters set within the frame, character size (length, width) T _X, the T _Y Figure 3 detected as (b), comparing this size P _X standard pattern, and P _Y. Further, the center of the cut pattern is detected (see FIG. 3 (b)), this center is matched with the center of the standard pattern, and matching (overlapping) is performed. determining consistency by comparing the reference area value M _S set in advance. Furthermore, the perimeter of the character is determined and compared with a reference value to determine consistency.

Here, an operation in the case where a data collection mode is designated in order to determine whether the reference value used in the determination is accurate in determining the consistency with each standard pattern will be described. First, a character position (position of a cutout frame) at which data should be collected is specified. Specify
One or all may be used. Since only digit bottommost in the example of such object of FIG 2 is changing, specifying a frame K ₄ shown in FIG. 3 (b), for example. Next, as shown in FIG. 4, a character Xk (a plurality of characters can be specified) from which data is to be collected, a standard pattern Pk similar to the character Xk are specified, and the number of determinations (the number of objects) is specified. The reception circuit 14 permits the reception of the reading start signal from the outside, and starts the determination. This reading start signal is a signal indicating that the object to be read has arrived in front of the television camera, and is not received by the reading start receiving circuit 14 when setting data for the data collection mode or during the data collection mode. .

FIG. 5 is a flowchart for explaining the operation in the data collection mode. First, step S1
In, the number m of the inspection target is initialized to start from “1”, and the determination processing of the inspection target “1” is performed in step S2. Then, the determination result R is determined whether the specified character Xk in step S3 (the process of identification in the claims
Corresponding), returns to the No (N), if the step S2, a similar standard pattern Pk preset for Yes (Y) if the specified character Xk, initialize the k in step S4 to begin _{P 1} I do. Then, in step S4
Is the same as the specified character and a standard
A feature is extracted by matching with the pattern. In step S51, the difference area Mk between the designated character Xk and the standard pattern Pk is calculated by using the difference area maximum value Mkmax
If Mk> Mkmax, Mk is updated as Mkmax in step S52; otherwise, the process proceeds to step S53, where the difference area M
k is compared with the previous difference area minimum value Mkmin. If Mk < Mkmin , Mk is updated as Mkmin in step S54, and if not, the process proceeds to step S61. When entering the data collection mode from the beginning, the previous value is “0”.
Therefore, both the maximum value and the minimum value are updated.

Hereinafter, the designated character Xk and the standard pattern Pk
The same processing as described above is performed for the size difference Tk and the perimeter difference Sk (see steps S61 to S64 and steps S71 to S74). The above processing is performed with the designated character Xk
Is repeated for each object for a predetermined number (n) of standard patterns Pk (see step S8), and processing for all objects (N) is performed (see step S10).
The result is displayed on the monitor 12 via, for example, the character data display circuit 11 in FIG. 1 so that the result can be used for correcting the set reference value. This data is retained until the next data collection mode starts. Also, the data is updated each time the data is collected (of course,
There is also). FIG. 6 shows an example of collected data. This is designated character Xk is _{X 1, X} 2 ... There i pieces and _{X i,} preset standard pattern Pk is _P 1 to P with respect to each
_{In the} case of _n and n pieces, the difference area maximum value, the minimum value, the size difference maximum value, the minimum value and the perimeter difference maximum value, the minimum value data are shown. Note that the optimum set value is determined based on such data, but the method of determining the optimum set value is omitted here because it has no direct relation.

[0011]

According to the present invention, by collecting the necessary data by designating the data collection mode, it is possible to easily collect a large amount of data based on a large number of determination results on the actual line. Since only the data can be displayed on the monitor, the set value can be accurately corrected based on this data, and the reading accuracy can be improved as compared with the conventional one.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a system configuration to which the present invention is applied.

FIG. 2 is an explanatory diagram for describing an example of an inspection object.

FIG. 3 is an explanatory diagram for explaining a cutout frame and a cutout example of characters;

FIG. 4 is an explanatory diagram for describing an example of a designated character and a setting standard pattern similar thereto.

FIG. 5 is a flowchart illustrating an operation in a data collection mode.

FIG. 6 is an explanatory diagram for explaining an example of collected data.

[Explanation of symbols]

 Reference Signs List 1 TV camera 2 Binarization circuit 3 Image memory 4 Address generation circuit 5 Projection extraction circuit 6 Address generation circuit 7 Standard pattern memory 8 Matching circuit 9 Processing device (CPU) 10 Bus 11 Character data display circuit 12 Monitor 13 Data memory 14 Read Start reception circuit 15 Keyboard

Claims (2)

(57) [Claims] An image of a plurality of unknown characters arranged in a predetermined direction on an individual object is taken, and each character pattern is cut out based on the taken image. When reading a character from the matching degree, a cutout frame corresponding to at least one character position among the unknown characters, and at least one cutout frame included in the cutout frame
A first step of designating one character (hereinafter referred to as a designated character); and a second step of selecting a character pattern similar to the designated character as a standard pattern from a plurality of preset standard patterns. A third step of receiving a data collection instruction to collect data on the designated character designated in the first step, and reading a character from the matching degree with the standard pattern selected in the second step; The result of the reading in the third step is one of the designated characters.
A fourth step of determining whether the character is one of the characters, and, if the reading result is identified as one of the designated characters designated in the second step by the fourth step,
A fifth step of extracting a feature quantity by obtaining a degree of matching between the designated character and the standard pattern selected in the second step; and selecting the data extracted in the fifth step in the second step. And storing the data stored in the memory for each standard pattern in a memory, wherein the data stored in the sixth step can be displayed on a monitor. 2. The processing of the data is prohibited from accepting the determination of the next object until the processing of all data is completed, and the determination of the next object is executed after the processing of all data is completed. 2. The character data collection method according to claim 1, wherein data collection is enabled by using a character string.